I'm trying to iterate over a "value" list and convert it into a string. Here is the code:
var blkstr = $.each(value, function(idx2,val2) {
var str = idx2 + ":" + val2;
alert(str);
return str;
}).get().join(", ");
alert() function works just fine and displays the proper value. But somehow, jquery's .get() function doesn't get the right sort of object and fails. What am I doing wrong?
If value is associative array, such code will work fine:
var value = { "aaa": "111", "bbb": "222", "ccc": "333" };
var blkstr = [];
$.each(value, function(idx2,val2) {
var str = idx2 + ":" + val2;
blkstr.push(str);
});
console.log(blkstr.join(", "));<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>(output will appear in the dev console)
As Felix mentioned, each() is just iterating the array, nothing more.
Converting From Array to String is So Easy !
var A = ['Sunday','Monday','Tuesday','Wednesday','Thursday']
array = A + ""
That's it Now A is a string. :)
You can use .toString() to join an array with a comma.
var array = ['a', 'b', 'c'];
array.toString(); // result: a,b,c
Or, set the separator with array.join('; '); // result: a; b; c.
not sure if this is what you wanted but
var arr = [A, B, C];
var arrString = arr.join(", ");
This results in the following output:
A, B, C
Four methods to convert an array to a string.
Coercing to a string
var arr = ['a', 'b', 'c'] + []; // "a,b,c"
var arr = ['a', 'b', 'c'] + ''; // "a,b,c"
Calling .toString()
var arr = ['a', 'b', 'c'].toString(); // "a,b,c"
Explicitly joining using .join()
var arr = ['a', 'b', 'c'].join(); // "a,b,c" (Defaults to ',' seperator)
var arr = ['a', 'b', 'c'].join(','); // "a,b,c"
You can use other separators, for example, ', '
var arr = ['a', 'b', 'c'].join(', '); // "a, b, c"
Using JSON.stringify()
This is cleaner, as it quotes strings inside of the array and handles nested arrays properly.
var arr = JSON.stringify(['a', 'b', 'c']); // '["a","b","c"]'
jQuery.each is just looping over the array, it doesn't do anything with the return value∆. You are looking for jQuery.map (I also think that get() is unnecessary as you are not dealing with jQuery objects):
var blkstr = $.map(value, function(val,index) {
var str = index + ":" + val;
return str;
}).join(", ");
But why use jQuery at all in this case? map only introduces an unnecessary function call per element.
var values = [];
for(var i = 0, l = value.length; i < l; i++) {
values.push(i + ':' + value[i]);
}
// or if you actually have an object:
for(var id in value) {
if(value.hasOwnProperty(id)) {
values.push(id + ':' + value[id]);
}
}
var blkstr = values.join(', ');
∆: It only uses the return value whether it should continue to loop over the elements or not. Returning a "falsy" value will stop the loop.
this's my function, convert object or array to json
function obj2json(_data){
str = '{ ';
first = true;
$.each(_data, function(i, v) {
if(first != true)
str += ",";
else first = false;
if ($.type(v)== 'object' )
str += "'" + i + "':" + obj2arr(v) ;
else if ($.type(v)== 'array')
str += "'" + i + "':" + obj2arr(v) ;
else{
str += "'" + i + "':'" + v + "'";
}
});
return str+= '}';
}
i just edit to v0.2 ^.^
function obj2json(_data){
str = (($.type(_data)== 'array')?'[ ': '{ ');
first = true;
$.each(_data, function(i, v) {
if(first != true)
str += ",";
else first = false;
if ($.type(v)== 'object' )
str += '"' + i + '":' + obj2json(v) ;
else if ($.type(v)== 'array')
str += '"' + i + '":' + obj2json(v) ;
else{
if($.type(_data)== 'array')
str += '"' + v + '"';
else
str += '"' + i + '":"' + v + '"';
}
});
return str+= (($.type(_data)== 'array')? ' ] ':' } ');;
}
var arr = new Array();
var blkstr = $.each([1, 2, 3], function(idx2,val2) {
arr.push(idx2 + ":" + val2);
return arr;
}).join(', ');
console.log(blkstr);
OR
var arr = new Array();
$.each([1, 2, 3], function(idx2,val2) {
arr.push(idx2 + ":" + val2);
});
console.log(arr.join(', '));
convert an array to a GET param string that can be appended to a url could be done as follows
function encodeGet(array){
return getParams = $.map(array , function(val,index) {
var str = index + "=" + escape(val);
return str;
}).join("&");
}
call this function as
var getStr = encodeGet({
search: $('input[name="search"]').val(),
location: $('input[name="location"]').val(),
dod: $('input[name="dod"]').val(),
type: $('input[name="type"]').val()
});
window.location = '/site/search?'+getStr;
which will forward the user to the /site/search? page with the get params outlined in the array given to encodeGet.
I needed an array to became a String rappresentation of an array I mean I needed that
var a = ['a','b','c'];
//became a "real" array string-like to pass on query params so was easy to do:
JSON.stringify(a); //-->"['a','b','c']"
maybe someone need it :)
working example
var arr = ['a', 'b', 'c', 1, 2, '3'];
// using toString method
var rslt = arr.toString();
console.log(rslt);
// using join method. With a separator '-'
rslt = arr.join('-');
console.log(rslt);
// using join method. without a separator
rslt = arr.join('');
console.log(rslt);Shouldn't confuse Array's with Lists... This is a list: {...} and has no length, or other Array properties.
This is an Array: [...] and you can use array functions, methods and so, like someone suggested here: someArray.toString();
"someObj.toString();" just will not work on any other objects type, like Lists. ;-)
Array.prototype.toString()
The toString() method returns a string representing the specified array and its elements.
var months = ["Jan", "Feb", "Mar", "Apr"];
months.toString(); // "Jan,Feb,Mar,Apr"
Syntax
arr.toString()
Return value
A string representing the elements of the array.
for more information :
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/toString
Here's an example using underscore functions.
var exampleArray = [{name: 'moe', age: 40}, {name: 'larry', age: 50}, {name: 'curly', age: 60}];
var finalArray = _.compact(_.pluck(exampleArray,"name")).join(",");
Final output would be "moe,larry,curly"
来源：https://stackoverflow.com/questions/5289403/convert-javascript-array-to-string